Method of preparing decorating mixtures



NrTED STATES PATENT Price.

MELVIN B. CHURCH, OF GRAND RAPIDS, MICHIGAN.

METHOD OF PREPARING DECORATING MIXTURES.

SPECIFICATION forming part of Letters Patent No. 513,003, dated January 16, 1894.

Application filed June 22, 1893. Serial No. 478.493. (lilo specimens.)

To ml? whom it may concern.-

3e it known that I, MELVIN B. CHURCH, a c t zen of the United States of America, res1d1ng at Grand Rapids, in the county of Kent and State of Michigan, have invented certain new and useful Improvements in Methods of Preparing Decorating Mixtures, of which the following is a specification.

My Invention relates to the manufacture of a composition or mixture of matter, designed ma nly for wall decoration of that class in which a base of calcined gypsum is mixed with glue, the whole being in a dry pulverized condition when put upon the market, and requiring the addition of water to reduce the composition or mixture to a condition required for use. These materials as used prior to the invention of Robert E. Haire, as shown in his appllcation, Serial No. 422,899, filed in the United States Patent Office on the 26th day of February, 1892, have required boiling water, or Very hot water to reduce them to a plastic or liquid condition. By theinvention of the said Haire the use of hotwater and the inconvenlences resulting therefrom, well known to the trade, have been avoided, the glue mixed with the calcined gypsum or other base, being in a condition of such fineness as to be reducible in cold water.

My invention herein set forth, consists of an improved mode of preparing the base and glue for reducing the glue to the extremely fine division required, having certain advan-- tages in respect to economy and convenience. I have used the method herein described in the mixing and preparation of calcined gypsum. The gypsum I take in the ordinary ground condition, and mix therewith evenly, the proper proportion of liquid glue. This proportion is from five (5) to eight (8) parts of the glue (a good quality is necessary) to one hundred parts of the base, it being understood that sufficient water is added to render the glue suitably liquid. After being mixed, the combined gypsum and glue are dried, to eliminate the water of the liquid glue. This should be done carefully, and special care be- 1ng taken not to allow the mixture to become heated high enough to impair the quality of the glue, that is, to impair its adhesiveness or solubility. This heat I keep below 212 Fahrenheit. After the parts have been evenly mixed, and dried, I then run the mixture through a grinding mill, preferably using for this work, the mill used for grinding calcined I gypsum in the manufacture of alabastine.

While I prefer the subsequent grinding of the mixture as described I desire it to be understood that this step may not always be found necessary as the mixture may be found to be sufficiently fine forimmediate use without the additional stepof grinding. The calcined gypsum and glue being thus ground together, the glue is reduced to an exceedingly fine condition, as fine as the base, and in this condition of impalpable powder,'the mixture may be reduced to a plastic or liquid and adhesive condition by the addition of cold water alone and is suitable to apply with a brush to make a firm and adhesive coating.

In practically working myinvention, I mix the base in a pulverized form with the liquid glue by any suitable means as by stirring the mixture, as the glue flows in. The mixtureis then subjected to heat in any suitable drier, and is afterward ground, as herein before explained.

The special discovery which is the basis of my invention herein explained, is that the liquid glue can be thus introduced in quantities sufficient to make the mixture adhesive, however prepared, and yet not require the recalcination of the gypsum, which would subjeot the glue to too great a degree of heat in order to drive off the water of crystallization.

Heretofore it has been supposed that water introduced with the glue into the calcined gypsum would be absorbed by the gypsum and become waterof crystallization,before it could be driven off. In the method above described the glue being a strong retarder the Water therein is not at once taken up by the gypsum. Oare must be taken, however, to drive off the water before absorption can take place. The water should be driven ofi within an hour after the glue has been introduced.

I prefer in practice to feed the glue into the calcined gypsum in the presence of heat so IOO I may use with the compound sulphate of zinc in the proportions of from one to two pounds of the sulphate of zinc to each ten pounds of gluethe proportions varying according to the quality of the glue, the proportions given being for good glue. Instead of the sulphate of zinc, I may use as equivalents, sulphuric acid or muriate of zinc. This has thoefiect to neutralize the fatty or organic matter of the glue, and regulates the setting of the compound; preventscracking in heavy relief work andalso acts as a preservative for theglue and as an antiseptic in the coating The sulphate of ziucmay when on the wall.

be added to the glue in process of manufactu'reorto theicornpound at any tlme.

I claim- 1. The herein described method of malnng an adhesive wall coating compound of animal glue and calcined gypsum, consisting in feeding the. liquid animal glue into the pulverized gypsum in the proportions, substantially as described, mixing the same by stirring as the glue isfed, and subjecting the mixture to heat to dry the same, substantially as described.

2. The herein described method of making ,an adhesivewallcoating compound of animal glue and calcined gypsum, consisting in mixing the liquid animal glue and pulverlzed gypsum together, driving off the water in the a glue before being absorbed by the gypsum by heat, and subsequently grinding the ingredients so mixed, substantially as described.

In testimony whereof I at'fix my signature in presence of two witnesses. MELVIN B. CHURCH.

Witnesses:

HENRY E. COOPER, WALTER DONALDSON. 

